Electromagnetically-operated device



ELECTROMAGNETICALLY OPERATED DEVICE Filed sept. 1. 1922 Ivefzor Patented Sept. 13, 1927.

UNITED STATES 1,642,288 PATENT OFFICE.

`CHESTER I). AINSWORTH, OF WOLLASTON, MASSACHUSETTS, ASSIGNOR, BY MESNE AS- SIGNMENTS, TVO CONDIT ELECTRICAL MANUFACTURING CORPORATION, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

ELECTROMAGNETICALLY-OPERATED DEVICE.

Application filed September 1, 1922. Serial No. 585,673.

This invention relates to electro-magnetically operated devices as, for instance, a potential-operated tripping device, adapted to control an electric switch, and has for an object to provide such `a device with simple and powerful force-increasing means adapted to be operated by the actuating element of the device. f

A further object is to provide the device with an improved actuating coil or solenoid having simple and effective means to anchor the coil terminals securely in place.

A further object is generally to improve the construction and operation of electromagnetically controlled devices.

Fig. 1 is a .side elevation of an undervoltage release device for an electric switch embodying my invention.

Fig. 2 is a transverse vertical section through the device.

Fig. 3 is a plan view of the device with the cover removed.

Fig. 4 is a sectional detail of the forcemultiplying mechanism;

Fig. 5 is a plan view of a Hange or head for the actuating solenoid.

Fig. 6 is a detail illustrating the end of the solenoid tube arranged to receive the head of Fig. 5.

l As here shown, my invention is applied to an under-Voltage release or tripping device adapted to effect the opening of an electric switch when the voltage of the circuit including the switch fails or becomes abnormally low in value, whereby to protect apparatus controlled by the switch, although the invention is not necessarily limited to such specific use.

The device here shown includes the casing 10 and the frame 1l which forms a cover for said casing. Both are secured together by suitable means, as screws l2, and the side wall 13 of said frame may be formed or provided with vertical recesses or chan nels 14 in which the heads of said screws are received.

Said casing 10 is adapted to receive and form a part of the magnetic circuit of the solenoid 15. Said solenoid includes the center tube 16 which, preferably, is of brass or other nonmagnetic material and may have the slot 17 extended through its side walls from end to end to reduce hysteresis and eddy current losses dueto the alternating Hux of the solenoid. A pole piece 18 of magnetic material is received and fixed in the upper end of said tube and is or may be formed with an outstanding Hange 19. Said pole piece also may be slotted to reduce hysteresis and eddy current losses therein. The lower wall 20 of said frame 11 is which said pole piece is movably received, and the bottom wall of said casing 10 is formed with an aligned aperture through which the lower end of said tube is movably extended. A spring washer 21 is disposed between the bottom wall of said casing and the solenoid, and is adapted to support the solenoid `yieldingly in position. The position of the solenoid within the casing is preferably such that the solenoid is free to vibrate vertically upon its spring support without Contact with the frame whereby t0 reduce the noise or hum inherent with a rigidly supported solenoid and its core when excited by an alternating current.

The wire comprising the solenoid is Vusually relatively small and consequently fragile and I prefer to provide the terminals of the solenoid of larger and mechanically stronger wire and it is an object of this invention to provide suitable means to anchor the terminals to the solenoid. For this purpose, l may wind a few turns of the heavy terminal wire 15a about one end of the insulating tube 25 of the solenoid prior to winding the finer wire composing the solenoid. Said tube is or maybe formed with the reduced end-portion 26 adapted to receive the anchor Hange 27 and a plain flange 28. Said anchor Hange may have a more or less circularly-formed aperture 29 adapted to receive the reduced end of the insulating tube 25 and a projection 30 may extend into said aperture 29 and be received in a corresponding notch 31 in the end 26 of said tube whereby to anchor said Hange against angular' movement on the tube. Said Hange 27 may also be formed with the aperture 32 which is or may be a continuation of the aperture 29, and a slot 33 may extend from said aperture 32 to the periphery of the Hange. Said Hange 27 is or may be approximatelyl as thick as the solenoid terminal and a solenoid terminal 15a is adapted to be received in the aperture 32 and slot 33 and. extend outwardly formed with an aperture in from the solenoid. The end flange 28 is received on the end oi the tube 25 and orms a cover Jfor the slot 33. If desired, a thin flange 34; may be interposed between the solenoid winding and the flange 27 whereby to cover the slot 33 on the winding side or" the flange 27. For certain purposes, the method of anchoring the solenoid terminal illustrated is satisfactory. For other purposes, the inner end ot the terminal 15n may be knotted in an obvious manner, not illustrated, and the knot received in the aperture 32 or the flange 27. The knot will be larger than the slot 33 and the terminal will consequently be held securely in place and all strain will be relieved from the fine wire ot the solenoid.A

A core or flange 35 of magnetic material, as iron, is movably received in the tube 16 of said solenoid and is adapted to be attracted upwardly and held against said pole piece 18 when the solenoid is energized, and drop downward when the solenoid is deenergized. A rod 86 is or may be secured in the upper end of said plunger and extend movably through an aperture 37 in the pole piece 118 and be provided at its upper end with a knob 38, which is or may be removably threaded or otherwise secured to the end of said rod. The lower end oi said rod,

Y or it .may be a nut ,39 carried by said rod,

or other means, forms an abutment of the plunger adapted to engage the power-multiplying mechanism whereby to operate it.

The force-multiplying mechanism is or may be contained mainly within the trame 11, which. is or may be of substantially circular formation to correspond to the forma- 4vtion of: the casing l0. Said torce-multiplying mechanism includes a cam lever adapted to be operated by the plunger 35, and a tripping Vlever adapted to be operated by the cam-lever to actuate the tripping mechanism ot' the switch. The cain-lever is bi- .furcated and the arms .l5 thereof are disposed on opposite sides of the plunger rod 36. The upper faces 45a of said arms are more or less arcuate in torni to provide cam faces adapted to be engaged by the abutment of said plunger rod. Said lever is pivoted on the pin 46 carried by the lbracket 47, Aand the arms of said bracket are received in slots in the side wall et said trame, and the bracket is or may be secured to said fra-me by the screw 48.

The tripping lever 50 is disposed beneath 'said cam lever and a roller 5l is pivoted on the pin 52 extended between the up-turned `side walls oi said tripping lever. Said roller is adapted to be engaged by the cam lever and depressed, whereby to operate the tripping mechanism of the switch. An aperture 53 is or may be 'formed in said lever 50 through which the plunger rod 36 is movably extended. The trame 1l is 'formed with a lateral extension 54 having a passage through it and said lever 50 is extended through said passage and pivoted on a pin 55 which is extended through aligned holes in the opposite side walls of the extension and the lever. Preferably a plurality of such aligned holes 56 are provided in the lever and extension and said pin 55 is adapted to be received in any set of aligned holes, whereby suitably to adjust the leverage and throw of said lever 50 Vfor a particular type of switch. Not only is the leverage of said lever 50 varied by this arrangement but the point of engagement between said lever and the cam lever is also varied whereby also to vary the multiplying eiiect of said lever system. spring 57 may encircle said pin and bear against said lever and a wall of said eX- tensioii and serve Ynormally to raise said tripping and cam levers, although said spring is adapted to be relatively light and not over-balance the weight of the plunger 35. The end of said. tripping lever is adapted to extend beyond the end ot the extension of said traine and may have the Vflat face kadapted to engage a latch a or equivalent oi a switch operating mechanism. The lever may also be otherwise formed for the purpose. c

Normally, the `solenoid l5 is energized and the plunger 35 is held in raised position and the spring 57 serves to hold the cam and tripping levers in the-dotted position illustrated ink Fig. l. Then he solenoid becomes cle-energized, as by failure or reduction of voltage in the circuit including said solenoid, said plunger is permitted to drop by gravity and its weight serves to depress the cam-lever and thereby actuate the tripping lever to open the switch. Upon re-energization of the solenoid the plunger is again moved upward and the spring 57 serves to restore said rlevers to their raised position.

It will be noted that the arrangement of compound levers herein provided, largely multiplies the tripping action of the device.

The recess in the frame 1l and the mechanism contained therein may be enclosed by i 'r the cover 60. Said cover may have the aperture 61 in which the shank of the knob 38 is movabiy received. Dowel pins 62 may be extended below the lower edge and are or may be adapted to enter the channels 14 of the frame whereby to center the cover in position, and a threaded rod 63 may be extended through said cover and be received in a threaded recess in the frame, whereby to secure the cover removably in position.

The frame 11 may be formed withthe attaching lug 65 by which the device may be secured to a fixed support and the frame may also be formed with the recess 66, for the passage of solenoid terminals.

" `The dev ice illustrated may also be arranged as a shunt trip, that is, it may be energized by a source of potential controlled by an automatic relay or a manually-open ated switch to trip the switch and cause it to open.l For this purpose, the spring 57 may be made of increased strength and serve to hold the plunger and force-multiplying levers in raised position against the action of gravity. The solenoid may be arranged to pull the plunger downwardly when energized and actuate the force-multiplying levers and effect the control of the switch.

i The construction may be otherwise modilied without departing from the spirit of the invention.

I' claim:

l. An electro-maonetically operated device comprising the combination of two overlapping co-acting levers arranged in alignment and pivotally supported beyond their overlapping regions, a solenoid disposed below said levers, and a solenoid-operated member disposed above the overlapping region of said levers and between their pivotal supports and arranged to descend and engage the uppermost lever, and thereby actuate the lowermost lever with increased force.

2. An electro-magnetically operated device comprising the combination of upper and lower force-multiplying levers, a solenoid disposed below said levers, and a plunger for said solenoid passed upwardly and freely through said levers and arranged to descend upon and engage said upper lever.

8. An electrdmagnetieally operated device comprising the combination of a frame, a solenoid depending therefrom, a plunger operable in said solenoid, two overlapping levers pivoted to said frame on opposite sides of said plunger and arranged to engage each other atrone side of said plunger, and said plunger arranged to engage one of said levers whereby to act upon the other lever with increased force.

4. An electro-magnetically operated device comprising the combination of a pair of superimposed levers bearing against each other a spring normally supporting said levers in elevated position, a solenoid, and avplunger therefor normally h eld in raised position and adapted to move downward into effective engagement with the uppermost lever and overpower said spring.

5. An electro-magnetically operated device comprising the combination of a frame having a recess and an extension having a passage therethrough, a tripping lever extended through said passage -and outwardly beyond said extension and pivoted to said extension, a second lever received in the recess of and pivoted to said frame opposite said extension and arranged having a continuous bearing againstthe inner end of the said first lever, a solenoid depending from said frame, and a plunger for said solenoid eX- tended into said frame-recess and arranged to operate said second lever. i

6. An electro-magnetically operated device comprising the combination of a frame having a recess andan extension having a passage therethrough, a tripping lever extended through said passa-ge and pivoted to said extension, said frame having a pair of slots in its side wall opposite said extension, a supporting member received in said slots and extended into the frame-recess, external means securing said supporting member to said frame, a second lever pivoted to said supporting member and overlying and engaging said iirst lever, a solenoid depending from said fra-me, and a plunger therefor extended into said frame-recess and arranged to operate said second lever.

`7. An electro-magnetically operated devi ce comprising the combination of a frame having a recess and an extension having a passage therethrough, a tripping lever ex tended through said passage and pivoted to said extension, said frame having a pair of slots in its side wall opposite said extension, supporting member received in said slots and extended into' the frameerecess, a second lever pivoted to said supporting member and overlying and engaging said 'lirst lever, a solenoid depending from said frame, and a plunger therefor extended into said frame and recess and arranged to operate said second lever.

8. An electro-magnetically operated device comprising the combination of a frame having a recess and an extension having a passage therethrough communicating with said recess, a lever extended through said passage and into said recess and pivoted to said extension, a solenoid depending from said frame, a plunger therefor having an extension extended into said recess and above said lever, a second lever superposed above said first lever in ysaid frame-recess and pivoted to said frame and having a' bifurcated end enclosing said plunger-extension, said rst lever arranged to be engaged with said second lever intermediate the ends of said second lever, and said plunger-ex tension' arranged to bear against the end of said second lever whereby to operate said first lever with increased force.

9. An electro-magnetically operated de vice comprising a. frame having an open recess in its upper face and a lateral aperture into said recess, a removable cover for said recess, a solenoid-casing removably depending from said frame, a solenoid in said casing, a plunger operable within said solenoid and having an extension extended up wardly into said frame-recess, a pair of co` acting overlapping levers disposed in said frame-recess and pivoted at opposite points to the frame, the lower lever having an lln flo

extension extended outwardly beyond the iframe through the lateral aperture therein, and said plunger-extension having a member overlying the upper lever and adapted to bear against it, whereby to operate the lower lever with increased force.

10. An electro-magnetically operated Vdevice comprising` a 'frame having an open recess in its upper face and a lateral aperture into said recess, a removable cover for Said recess, a. solenoid-casing removably depending from said frame, a solenoid in said casing, a plunger operable within said solenoid and having` an extension extended upwardly into said frame-recess, a pair of co-aoting overlapping levers disposed in said flame-recess and pivoted at opposite points to the frame, the lower lever having an extension extended outwardly beyond the frame through the lateral aperture therein, and said plunger-extension having a member overlying the upper lever and adapted to beur against it, whereby to operate the lower lever with increased force., said plungenextension also extended freely through said cover and terminated in an exposed manually-engageable member.

1l. An electrosmagnetically operateddevice including a frame having a plurality of iiieripherally-spaced vertical channelsin its side walls, a casingdepending from said frame and having attaching screws disposed in the lower portion of sai-d frame-channels, a cover disposed upon said frame having a plurality of depending centering-pins disposed in the upper portions of said frame-channels, and a cover locking member releasingly securing said cover to said frame.

12. An electro-magnetically operated device including a 'frame having a recess, a; channeled lever disposed in said recess and pivoted to said frame, a roller disposed in the channel of said lever and pivotaHy supported at one end thereof, a pivoted bifurcated lever disposed above said channeled lever and roller and in position to engage said? roller, a solenoid disposed below said iframe, a plunger operable in said solenoid having` an upward extension disposed between the furcations of said biurcated lever and a head on said extension. extended over and in position to engage said urcations.

ln testimony whereof, I have signed my name to this speciication.

CHESTER D.` AIN SWGRTH. 

